There is often a need to perform coating operations in small "job shops" where glass fiber duct board and similar workpieces are cut and fabricated into ductwork for heating, ventilating and air conditioning systems. While workpieces such as glass fiber duct boards are sometimes coated by the duct board manufacturer to encapsulate glass fibers and dust within the duct boards prior to the shipment of the duct boards to the job shops, the cutting of grooves in the duct boards at the job shops during the fabrication of the ductwork exposes glass fibers and dust in the groove surfaces. Accordingly, there has been a need to coat the surfaces of the grooves formed in the duct boards to encapsulate the glass fibers and any dust created during the grooving operation within the surfaces of the grooves.
Conventional low volume foam generators are available that could perform this foaming operation. However, these conventional low volume foam generators typically sell for over $13,000.00 and many of the small job shops can not afford such an expenditure. Thus, there has been a need for a simple, low cost, effective foam generator to serve this market. The foam generator of the present invention, which would cost about $1,000.00 or less, satisfies the needs of this relatively low volume, job shop market where, typically, about 8 drums of a liquid polymeric coating per year would be utilized by the ductwork fabricator.